Apparatus for endoscopic procedures

ABSTRACT

A surgical device includes a jaw assembly, an articulating assembly and a drive shaft. The jaw assembly includes first and second jaws. The articulating assembly is removably coupled to a proximal end of the jaw assembly and includes a distal joint member, a proximal joint member, and a pivot pin. The pivot pin is fixedly coupled to the distal joint member and is rotatably coupled to the proximal joint member. The jaw assembly and the distal joint member together define a first longitudinal axis. The proximal joint member defines a second longitudinal axis. The drive shaft includes a gear element that is meshingly engaged with a pivoting gear element that is fixedly coupled to the pivot pin. Longitudinal movement of the first drive shaft pivots the jaw assembly relative to the proximal joint member about a pivot axis defined by the pivot pin.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation-in-Part of U.S. patentapplication Ser. No. 16/158,427, filed Oct. 12, 2018, which claims thebenefit of U.S. Provisional Patent Application Ser. No. 62/578,673,filed Oct. 30, 2017, the entire contents of which are incorporated byreference herein.

TECHNICAL FIELD

The present disclosure relates to surgical apparatus, devices and/orsystems for performing endoscopic surgical procedures and methods of usethereof. More specifically, the present disclosure relates to manual,electromechanical, robotic and/or hand-held surgical apparatus, devicesand/or systems configured for use with removable disposable loadingunits and/or single use loading units for clamping, cutting and/orstapling tissue.

BACKGROUND

A number of surgical device manufacturers have developed product lineswith proprietary drive systems for operating and/or manipulatingelectromechanical surgical devices. In many instances theelectromechanical surgical devices include a handle assembly, which isreusable, and disposable loading units and/or single use loading unitsor the like that are selectively connected to the handle assembly priorto use and then disconnected from the handle assembly following use inorder to be disposed of or in some instances sterilized for re-use.

Various electromechanical linkages are utilized to transmit power fromthe reusable handle assemblies, which include one or more motors, to thedisposable loading unit to effect rotation, pivoting, clamping, fastenerejection, etc. Due to the complex structure and operation of the powertransmission mechanisms inadvertent actuation of these mechanisms mayresult in unintended operation of the disposable loading unit, which mayresult in damage to the surgical device and/or injury to the patient.Robotic systems for performing minimally invasive surgery are alsoknown. For example, International Application Publication WO 2000/051486discloses a system having remotely-controlled surgical instruments.

Many of these electromechanical surgical devices are relativelyexpensive to manufacture, purchase and/or operate. There is a constantdesire by manufacturers and end users to develop electromechanicalsurgical devices that are relatively inexpensive to manufacture,purchase and/or operate that still provide a large degree of operabilitywith prerequisite safety features. Accordingly, a need exists forelectromechanical surgical apparatus, devices and/or systems thatinclude effective electromechanical transmission system for actuatingthe disposable units as well as safety lockout assemblies.

SUMMARY

In a first aspect of the present disclosure, a surgical staplinginstrument comprises a reload including a staple cartridge assembly andan anvil assembly moveable with respect to one another. An adapterassembly has an elongate shaft and an articulating distal end, amounting member being disposed at the distal end and being pivotallyattached to the elongate shaft, the mounting member having a connectionfeature for attaching the reload to the adapter assembly. A drivemechanism is in the adapter, the drive mechanism including a barextending through the mounting member and having a beam at a distal endof the bar, the bar being flexible and supported by a pair of barguides, one of the bar guides alongside a first side of the bar, and theother of the bar guides being alongside a second side of the bar, thebar being further supported by a pair of blowout plates, one of theblowout plates being alongside the first side of the bar, and the otherof the blowout plates being alongside the second side of the bar, thepair of blowout plates being distal to the pair of bar guides, the barbeing further supported by a support block having an opening, the barand the pair of blowout plates being disposed in the opening of thesupport block, the bar, the pair of bar guides, the pair of blowoutplates, and the support block being pivotable from a central position inthe adapter assembly to an off-center position in the adapter assembly.

The support block can be curved. The mounting member can have a curvedslot. The support block can be disposed in the curved slot so that thesupport block is movable in the curved slot.

An articulation link extends inside the elongate shaft, and a secondlink pivotally connected to the articulation link and to the mountingmember. The second link can be curved.

The bar can have a plurality of layers stacked together. The beam canhave an upper flange and a lower flange. The bar can be attached to athreaded drive member. The threaded drive member may be disposed insidean inner tube having an interior thread. The connection feature candefine a keyway. The reload may define a tab that is received in thekeyway.

In another aspect, a surgical stapling system comprises: a hand-heldinstrument handle having a battery, a motor and computer and memorycomponents; a removable and replaceable adapter assembly; a first linearsurgical stapling reload having a first end effector, the first linearsurgical stapling reload being removably and replaceably attachable tothe adapter assembly; and a second linear surgical stapling reloadhaving a second end effector and being removably and replaceablyattachable to the adapter assembly, the second linear surgical staplingreload having a feature and the first linear stapling reload not havingthe feature, each of the first linear surgical stapling reload and thesecond linear surgical stapling reload having a staple cartridgeassembly and an anvil assembly.

The adapter assembly corresponds to the first linear surgical staplingreload and the second linear surgical stapling reload. The feature canbe a dissecting tip on a distal end of the anvil assembly of the secondlinear surgical stapling reload.

The feature can be a stapling buttress on each of the anvil assembly andthe staple cartridge assembly of the second linear surgical staplingreload.

The handle can be sterilizable and re-used for a prescribed number ofprocedures.

In accordance with yet another aspect of the present disclosure, asurgical stapling system including a cartridge assembly is provided. Thecartridge assembly includes a cartridge and a sled assembly configuredto drive fasteners through the cartridge. The cartridge has atissue-contacting surface. The sled assembly includes a knife pivotallycoupled to the sled assembly. The knife has a blade and is positioned topivot distally from a first position where the blade is disposed belowthe tissue-contacting surface to a second position where the blade isdisposed above the tissue-contacting surface.

In some embodiments, the sled assembly may include knife mount that hasa blocking surface. The blocking surface may extend over the knife andmay be positioned to support the knife in the second position. The knifemay include a knife arm that is coupled to the knife mount by a pivotpin to enable the knife to pivot relative to the knife mount. The knifemay be coupled to a spring that is engaged with the knife mount andpositioned to urge a distal foot of the knife arm distally so that theblade, which is supported on a proximal portion of the knife arm, isurged toward the first position. The knife mount may include astabilizing finger that extends from the knife mount to support theknife when the knife is in the second position.

Further details and aspects of exemplary embodiments of the presentdisclosure are described in more detail below with reference to theappended figures.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present disclosure are described herein withreference to the accompanying drawings, wherein:

FIG. 1 is a perspective, disassembled view of an electromechanicalsurgical system including a surgical instrument, an adapter assembly,and an end effector, according to the present disclosure;

FIG. 2 is a perspective view of the surgical instrument of FIG. 1,according to the present disclosure;

FIG. 3 is perspective, disassembled view of the surgical instrument ofFIG. 1, according to the present disclosure;

FIG. 4 is a perspective view of a battery of the surgical instrument ofFIG. 1, according to the present disclosure;

FIG. 5 is a top, partially-disassembled view of the surgical instrumentof FIG. 1, according to the present disclosure;

FIG. 6 is a front, perspective view of the surgical instrument of FIG. 1with the elongated member separated therefrom, according to the presentdisclosure;

FIG. 7 is a cross-sectional side view of the surgical instrument of FIG.1, as taken through 7-7 of FIG. 1, according to the present disclosure;

FIG. 8 is a top, cross-sectional view of the surgical instrument of FIG.1, as taken through 8-8 of FIG. 1, according to the present disclosure;

FIG. 9 is a perspective, disassembled view of a control assembly of thesurgical instrument of FIG. 1, according to the present disclosure;

FIG. 10 is a perspective view of the adapter assembly of FIG. 1 havingan articulating neck assembly, according to the present disclosure;

FIG. 11 is a perspective, partial cross-sectional view of the adapterassembly of FIG. 1, according to the present disclosure;

FIG. 12 is a perspective view of an end effector connected to a distalend of the adapter assembly of FIG. 1, oriented in a linear,non-articulated orientation, according to the present disclosure;

FIG. 13 is a disassembled view of the end effector of FIG. 12, accordingto the present disclosure;

FIG. 14 is a perspective, cross-sectional view of the end effector ofFIG. 12, according to the present disclosure;

FIG. 15 is an enlarged, cross-sectional side view of the end effector ofFIG. 12, according to the present disclosure;

FIG. 16 is an enlarged, cross-sectional side view of the end effector ofFIG. 12 disconnected from the articulating neck assembly, according tothe present disclosure;

FIG. 17A is a disassembled view of the articulating neck assemblyaccording to the present disclosure;

FIG. 17B is a perspective view of part of the articulating neck assemblyaccording to the present disclosure;

FIG. 18 is a top perspective, partially-disassembled view of thearticulating neck assembly according to the present disclosure;

FIG. 19 is a bottom perspective, partially-disassembled view of thearticulating neck assembly according to the present disclosure;

FIG. 20 is a side perspective, partially-disassembled view of thearticulating neck assembly according to the present disclosure;

FIG. 21 is a top perspective, partially-disassembled view of thearticulating neck assembly according to the present disclosure;

FIG. 22 is a top perspective view of the articulating neck assemblyaccording to the present disclosure;

FIG. 23 is a side view of the articulating neck assembly in anarticulated orientation, according to the present disclosure;

FIG. 24 is an enlarged, cross-sectional side view of the end effector ofFIG. 12 connected to the articulating neck assembly, according to thepresent disclosure;

FIG. 25 is a cross-sectional side view of the end effector of FIG. 12connected to the articulating neck assembly oriented in a linear,non-articulated orientation, according to the present disclosure;

FIG. 26 is a cross-sectional side view of the end effector of FIG. 12connected to the articulating neck assembly oriented in a firstarticulated orientation, according to the present disclosure;

FIG. 27 is a cross-sectional side view of the end effector of FIG. 12connected to the articulating neck assembly oriented in a secondarticulated orientation, according to the present disclosure;

FIG. 28 is a perspective view of another embodiment of an articulatingneck assembly with an end effector connected to a distal end of theadapter assembly of FIG. 1, oriented in a linear, non-articulatedorientation, according to the present disclosure;

FIG. 29 is a perspective, disassembled view of the articulating neckassembly of FIG. 28 according to the present disclosure;

FIG. 30 is a top perspective, partially-disassembled view of thearticulating neck assembly of FIG. 28 according to the presentdisclosure;

FIG. 31 is a cross-sectional, side view of the end effector connected tothe articulating neck assembly of FIG. 28 oriented in a linear,non-articulated orientation, according to the present disclosure;

FIG. 32 is a cross-sectional, side view of the end effector connected tothe articulating neck assembly of FIG. 28 oriented in a firstarticulated orientation, according to the present disclosure;

FIG. 33 is a cross-sectional, side view of the end effector connected tothe articulating neck assembly of FIG. 28 oriented in a secondarticulated orientation, according to the present disclosure;

FIG. 34 is a perspective view of a surgical stapling instrumentaccording to another aspect of the present disclosure:

FIG. 34A is an elevation view of the end effector reload and the distalend of the adapter assembly;

FIG. 35 is a perspective view of an adapter assembly and an end effectorreload for the surgical stapling instrument;

FIG. 36 is a cross-sectional view of the adapter assembly for thesurgical stapling instrument of FIGS. 34-35;

FIG. 37 is a perspective view of the articulating portion of the adapterassembly;

FIG. 38 is a cross-sectional view of the articulating portion of theadapter assembly;

FIG. 39 is a perspective view of the articulating portion of the adapterassembly;

FIG. 39A is a cross-sectional view of the proximal end of the adapterassembly;

FIG. 39B is a perspective view of the lead screw of the adapterassembly;

FIG. 40 is a perspective view of an I-beam for the surgical staplinginstrument;

FIG. 40A is a perspective view of the I-beam and sled for the surgicalstapling instrument;

FIG. 40B is a perspective view of the I-beam and sled for the surgicalstapling instrument;

FIG. 41 is a perspective view of the articulation mechanism in theproximal end of the adapter assembly;

FIG. 42 is a cross-sectional view of the articulation mechanism in theproximal end of the adapter assembly;

FIG. 43 is a plan view of the articulation mechanism in the distal endof the adapter assembly;

FIG. 44 is a plan view of the articulation mechanism in the distal endof the adapter assembly;

FIG. 45 is a perspective view of the articulation mechanism in thedistal end of the adapter assembly;

FIG. 45A is a perspective view of a gear assembly in the adapterassembly;

FIG. 46 is a perspective view of the end effector reload and distal endof the adapter assembly;

FIG. 47 is a perspective view of the proximal end of the end effectorreload;

FIG. 48 is a plan view of the end effector reload and distal end of theadapter assembly;

FIG. 48A is a cross-sectional view of the end effector reload and distalend of the adapter assembly;

FIG. 49 is a perspective view of the adapter assembly and end effectorreload showing the reload unattached to the adapter assembly;

FIG. 50 is an exploded view of the staple cartridge assembly and anvilassembly;

FIG. 51 is a plan view of a different example of an articulationmechanism in the distal end of an adapter assembly;

FIG. 52 is a perspective view of another embodiment of an end effectorof the electromechanical surgical system of FIG. 1, the end effectorillustrated in an unclamped position;

FIG. 52A is a perspective view illustrating the end effector of FIG. 52secured to the electromechanical surgical system of FIG. 1;

FIG. 53 is a perspective view of the end effector of FIG. 52 with acartridge assembly of the end effector shown separated from a toolassembly of the end effector;

FIG. 54 is a perspective view, with parts separated, of the cartridgeassembly of FIG. 53;

FIG. 55 is an enlarged perspective view of a sled assembly of thecartridge assembly of FIG. 54, the sled assembly including a blade shownin a first position;

FIG. 56 is a perspective view of the sled assembly of FIG. 55 with theblade thereof shown in a second position;

FIG. 57 is a side, cross-sectional view of the sled assembly of FIGS. 55and 56 as taken along section line 57-57 seen in FIG. 55;

FIG. 58 is a side, cross-sectional view of the sled assembly of FIGS. 55and 56 as taken along section line 58-58 seen in FIG. 56;

FIG. 59 is a perspective view, with parts separated, of the sledassembly of FIGS. 55 and 56;

FIG. 60 is a side, cross-sectional view of the end effector of FIG. 52as taken along section line 60-60 shown in FIG. 52A, the end effectorshown in a clamped position;

FIGS. 61-62 are enlarged progressive views of the indicated area ofdetail shown in FIG. 60; and

FIG. 63 is a perspective view illustrating the blade of the sledassembly of FIGS. 55 and 56 in the second position and engaged with anI-beam of the end effector of FIG. 52.

DETAILED DESCRIPTION

Embodiments of the presently disclosed electromechanical surgicalsystem, apparatus and/or device are described in detail with referenceto the drawings, in which like reference numerals designate identical orcorresponding elements in each of the several views. As used herein theterm “distal” refers to that portion of the electromechanical surgicalsystem, apparatus and/or device, or component thereof, that are fartherfrom the user, while the term “proximal” refers to that portion of theelectromechanical surgical system, apparatus and/or device, or componentthereof, that are closer to the user. The terms “left” and “right” referto that portion of the electromechanical surgical system, apparatusand/or device, or component thereof, that are on the left and rightsides, respectively, from the perspective of the user facing the distalend of the electromechanical surgical system, apparatus and/or devicefrom the proximal end while the surgical system, apparatus and/or deviceis oriented in non-rotational configuration.

Reference may be made to International Application Publication No. WO2009/039506, U.S. Pat. No. 9,775,610, and U.S. Patent ApplicationPublication US 2011/0121049, the entire contents of each of which areincorporated by reference herein, for a detailed description of theconstruction and operation of exemplary electromechanical, hand-held,powered surgical instrument 100.

Referring initially to FIGS. 1-8, an electromechanical, hand-held,powered surgical system, in accordance with an embodiment of the presentdisclosure is shown and generally designated 10. Electromechanicalsurgical system 10 includes a surgical apparatus or device in the formof an electromechanical, hand-held, powered surgical instrument 100 thatis configured for selective attachment thereto of a plurality ofdifferent end effectors 300, via an adapter assembly (e.g., elongatedbody) 200. The end effector 300 and the adapter assembly 200 areconfigured for actuation and manipulation by the electromechanical,hand-held, powered surgical instrument 100. In particular, the surgicalinstrument 100, the adapter assembly 200, and the end effector 300 areseparable from each other such that the surgical instrument 100 isconfigured for selective connection with adapter assembly 200, and, inturn, adapter assembly 200 is configured for selective connection withany one of a plurality of different end effectors 300.

The end effector and/or adapter can be configured as an integral unit inany of the embodiments disclosed herein. The end effector and/or adaptercan be configured for use with a powered handle, console, and/orsurgical robot, in any of the embodiments disclosed herein.

As illustrated in FIGS. 1-3, the hand-held surgical instrument 100includes a handle housing 102 having a lower housing portion 104, anintermediate housing portion 106 extending from and/or supported onlower housing portion 104, and an upper housing portion 108 extendingfrom and/or supported on intermediate housing portion 106. Intermediatehousing portion 106 and upper housing portion 108 are separated into adistal half-section 110 a that is integrally formed with and extendingfrom the lower portion 104, and a proximal half-section 110 bconnectable to distal half-section 110 a by a plurality of fasteners.When joined, distal and proximal half-sections 110 a, 110 b define ahandle housing 102 having a cavity 102 a therein in which a circuitboard 150 and a drive mechanism 160 are situated.

With reference to FIGS. 2 and 3, distal and proximal half-sections 110a, 110 b are divided along a vertical plane that traverses alongitudinal axis “A-A” of upper housing portion 108 (FIG. 2). Handlehousing 102 includes a gasket 112 extending completely around a rim ofdistal half-section and/or proximal half-section 110 a, 110 b and beinginterposed between distal half-section 110 a and proximal half-section110 b. Gasket 112 seals the perimeter of distal half-section 110 a andproximal half-section 110 b. Gasket 112 functions to establish anair-tight seal between distal half-section 110 a and proximalhalf-section 110 b such that circuit board 150 and drive mechanism 160are protected from sterilization and/or cleaning procedures.

In this manner, the cavity 102 a of handle housing 102 is sealed alongthe perimeter of distal half-section 110 a and proximal half-section 110b yet is configured to enable easier, more efficient assembly of circuitboard 150 and a drive mechanism 160 in handle housing 102.

Intermediate housing portion 106 of handle housing 102 provides ahousing in which circuit board 150 is situated. Circuit board 150 isconfigured to control the various operations of surgical instrument 100,as will be set forth in additional detail below.

Lower housing portion 104 of surgical instrument 100 defines an aperture(not shown) formed in an upper surface thereof and which is locatedbeneath or within intermediate housing portion 106. As shown in FIGS. 3and 4, the aperture of lower housing portion 104 provides a passagethrough which wires 152 pass to electrically interconnect electricalcomponents situated in lower housing portion 104, e.g., a battery 156and a circuit board 154, with electrical components situated inintermediate housing portion 106 and/or upper housing portion 108, e.g.,circuit board 150, drive mechanism 160, etc.

Handle housing 102 includes a gasket 107 disposed within the aperture oflower housing portion 104 thereby plugging or sealing the aperture oflower housing portion 104 while allowing wires 152 to pass therethrough(see FIG. 3). Gasket 107 functions to establish an air-tight sealbetween lower housing portion 106 and intermediate housing portion 108such that circuit board 150 and drive mechanism 160 are protected fromsterilization and/or cleaning procedures.

With continued reference to FIGS. 3 and 4, lower housing portion 104 ofhandle housing 102 provides a housing in which the battery 156 isremovably disposed therein. The battery 156 may be a rechargeablebattery (e.g., lead-based, nickel-based, lithium-ion based, etc.). It isalso envisioned that the battery 156 may be a single-use,non-rechargeable battery. Battery 156 is configured to supply power toany of the electrical components of surgical instrument 100. Lowerhousing portion 104 defines a cavity (not shown) into which battery 156is inserted. Lower housing portion 104 includes a door 105 pivotallyconnected thereto for closing cavity of lower housing portion 104 andretaining battery 156 therein.

With continued reference to FIGS. 3 and 5, distal half-section 110 a ofupper housing portion 108 defines a nose or connecting portion 108 a. Anose cone 114 is supported on nose portion 108 a of upper housingportion 108. Nose cone 114 is fabricated from a transparent,light-transmissive material. An illumination member 116 is disposedwithin nose cone 114 such that illumination member 116 is visibletherethrough. The nose cone 114 may be tinted, such that theillumination member 116 is visible when it is activated.

With reference to FIG. 5, the illumination member 116 may include aplurality of any suitable light emitting devices, such as light emittingdiodes (LEDs), disposed on printed circuit board (LED PCB) 116 a whichis disposed in a vertical plane transverse to the longitudinal axis“A-A.” The illumination member 116 is configured to illuminate inmultiple colors with a specific color pattern being associated with aunique discrete event. In embodiments, the LEDs may be single-color ormulti-color LEDs.

Upper housing portion 108 of handle housing 102 provides a housing inwhich drive mechanism 160 is situated. As illustrated in FIG. 5, drivemechanism 160 is configured to drive shafts and/or gear components inorder to perform the various operations of surgical instrument 100. Inparticular, drive mechanism 160 is configured to drive shafts and/orgear components in order to selectively move tool assembly 304 of endeffector 300 relative to the adapter assembly, to rotate end effector300 about the longitudinal axis “A-A” (FIG. 2) relative to handlehousing 102, to move anvil assembly 306 relative to cartridge assembly308 of end effector 300, and/or to fire a stapling and cutting cartridgewithin cartridge assembly 308 of end effector 300.

The drive mechanism 160 includes a selector gearbox assembly 162 that islocated immediately proximal relative to adapter assembly 200. Proximalto the selector gearbox assembly 162 is a function selection module 163having a first (e.g., selector) motor 164 that functions to selectivelymove gear elements within the selector gearbox assembly 162 intoengagement with an input drive component 165 having a second (e.g.,drive) motor 166.

As illustrated in FIGS. 1-4, distal half-section 110 a of upper housingportion 108 defines a connecting portion 108 a configured to accept acorresponding shaft coupling assembly 214 of adapter assembly 200.

As illustrated in FIGS. 6-8, connecting portion 108 a of surgicalinstrument 100 has a cylindrical recess 108 b that receives the adapterassembly 200 when adapter assembly 200 is mated to surgical instrument100. Connecting portion 108 a houses three rotatable drive connectors118, 120, 122.

With reference to FIG. 6, when adapter assembly 200 is mated to surgicalinstrument 100, each of rotatable drive connectors 118, 120, 122 ofsurgical instrument 100 couples with a corresponding rotatable connectorsleeve 218, 220, 222 of adapter assembly 200. In this regard, theinterface between corresponding first drive connector 118 and firstconnector sleeve 218, the interface between corresponding second driveconnector 120 and second connector sleeve 220, and the interface betweencorresponding third drive connector 122 and third connector sleeve 222are keyed such that rotation of each of drive connectors 118, 120, 122of surgical instrument 100 causes a corresponding rotation of thecorresponding connector sleeve 218, 220, 222 of adapter assembly 200.

In the above-described embodiments, the hand-held surgical instrument100 may include a first (e.g., selector) motor 164 that functions toselectively move the selector gearbox assembly 162 gears into engagementwith an input drive component having a second (e.g., drive) motor. Inembodiments, other motor arrangements may be used, such as a differentmotor may be used for driving each of the connector sleeves. In furtherembodiments, other driving mechanisms for actuating the connectorsleeves may be used, including, but not limited to, pneumatic and/orhydraulic drivers, solenoids, biasing members, and combinations thereof.

The mating of drive connectors 118, 120, 122 of surgical instrument 100with connector sleeves 218, 220, 222 of adapter assembly 200 allowsrotational forces to be independently transmitted via each of the threerespective connector interfaces. The drive connectors 118, 120, 122 ofsurgical instrument 100 are configured to be independently rotated bydrive mechanism 160. In this regard, the function selection module 163of drive mechanism 160 selects which drive connector or connectors 118,120, 122 of surgical instrument 100 is to be driven by the input drivecomponent 165 of drive mechanism 160. The selector gearbox assembly 162and the function selection module 163 are disclosed in more detail in acommonly-owned U.S. patent application Ser. No. 13/280,898, the entirecontents of which is hereby incorporated by reference herein.

Since each of drive connectors 118, 120, 122 of surgical instrument 100has a keyed and/or substantially non-rotatable interface with respectiveconnector sleeves 218, 220, 222 of adapter assembly 200, when adapterassembly 200 is coupled to surgical instrument 100, rotational force(s)are selectively transferred from drive mechanism 160 of surgicalinstrument 100 to adapter assembly 200.

The selective rotation of drive connector(s) 118, 120 and/or 122 ofsurgical instrument 100 allows surgical instrument 100 to selectivelyactuate different functions of end effector 300. As discussed in greaterdetail below, selective and independent rotation of first driveconnector 118 of surgical instrument 100 corresponds to the selectiveand independent opening and closing of tool assembly 304 of end effector300, and driving of a stapling/cutting component of tool assembly 304 ofend effector 300. Also, the selective and independent rotation of seconddrive connector 120 of surgical instrument 100 corresponds to theselective and independent articulation of tool assembly 304 of endeffector 300 about an articulation axis “B-B” defined by a pin 505 (FIG.12) that is transverse to longitudinal axis “A-A” (FIG. 2). Inparticular, the end effector 300 defines a second longitudinal axis“C-C” and is movable from a first position in which the secondlongitudinal axis “C-C” (FIG. 12) is substantially aligned with thefirst longitudinal axis “A-A” to at least a second position in which thesecond longitudinal axis “C-C” is disposed at a non-zero angle withrespect to the first longitudinal axis “A-A.” Additionally, theselective and independent rotation of third drive connector 122 ofsurgical instrument 100 corresponds to the selective and independentrotation of end effector 300 about longitudinal axis “A-A” relative tohandle housing 102 of surgical instrument 100.

As illustrated in FIGS. 5 and 8, drive mechanism 160 includes a selectorgearbox assembly 162; a function selection module 163, located proximalto the selector gearbox assembly 162, that functions to selectively movegear elements within the selector gearbox assembly 162 into engagementwith second motor 166. Thus, drive mechanism 160 selectively drives oneof drive connectors 118, 120, 122 of surgical instrument 100 at a giventime.

As illustrated in FIGS. 1-3 and FIG. 9, handle housing 102 supports acontrol assembly 103 on a distal surface or side of intermediate housingportion 108. Control assembly 103, in cooperation with intermediatehousing portion 108, supports a pair of finger-actuated control buttons124, 126 and rocker devices 128, 130. In particular, control assembly103 defines an upper aperture 124 a for slidably receiving a firstcontrol button 124, and a lower aperture 126 b for slidably receiving asecond control button 126.

Each one of the control buttons 124, 126 and rocker devices 128, 130includes a respective magnet (not shown) that is moved by the actuationof an operator. In addition, circuit board 150 includes, for each one ofthe control buttons 124, 126 and rocker devices 128, 130, respectiveHall-effect switches 150 a-150 d that are actuated by the movement ofthe magnets in the control buttons 124, 126 and rocker devices 128, 130.In particular, located immediately proximal to the control button 124 isa first Hall-effect switch 150 a (FIGS. 3 and 7) that is actuated uponthe movement of a magnet within the control button 124 upon the operatoractuating control button 124. The actuation of first Hall-effect switch150 a, corresponding to control button 124, causes circuit board 150 toprovide appropriate signals to function selection module 163 and inputdrive component 165 of the drive mechanism 160 to close a tool assembly304 of end effector 300 and/or to fire a stapling/cutting cartridgewithin tool assembly 304 of end effector 300.

Also, located immediately proximal to rocker device 128 is a secondHall-effect switch 150 b (FIGS. 3 and 7) that is actuated upon themovement of a magnet (not shown) within rocker device 128 upon theoperator actuating rocker device 128. The actuation of secondHall-effect switch 150 b, corresponding to rocker device 128, causescircuit board 150 to provide appropriate signals to function selectionmodule 163 and input drive component 165 of drive mechanism 160 toarticulate tool assembly 304 relative to the adapter assembly 200.Advantageously, movement of rocker device 128 in a first directioncauses tool assembly 304 to articulate relative to the adapter assembly200 in a first direction, while movement of rocker device 128 in anopposite, e.g., second, direction causes tool assembly 304 to articulaterelative to the adapter assembly 200 in an opposite, e.g., second,direction.

Furthermore, located immediately proximal to control button 126 is athird Hall-effect switch 150 c (FIGS. 3 and 7) that is actuated upon themovement of a magnet (not shown) within control button 126 upon theoperator actuating control button 126. The actuation of thirdHall-effect switch 150 c, corresponding to control button 126, causescircuit board 150 to provide appropriate signals to function selectionmodule 163 and input drive component 165 of drive mechanism 160 to opentool assembly 304 of end effector 300.

In addition, located immediately proximal to rocker device 130 is afourth Hall-effect switch 150 d (FIGS. 3 and 7) that is actuated uponthe movement of a magnet (not shown) within rocker device 130 upon theoperator actuating rocker device 130. The actuation of fourthHall-effect switch 150 d, corresponding to rocker device 130, causescircuit board 150 to provide appropriate signals to function selectionmodule 163 and input drive component 165 of drive mechanism 160 torotate end effector 300 relative to handle housing 102 surgicalinstrument 100. Specifically, movement of rocker device 130 in a firstdirection causes end effector 300 to rotate relative to handle housing102 in a first direction, while movement of rocker device 130 in anopposite, e.g., second, direction causes end effector 300 to rotaterelative to handle housing 102 in an opposite, e.g., second, direction.

Turning now to FIGS. 1 and 10, adapter assembly 200 will be shown indetail and described. Adapter assembly 200 is configured to communicatethe rotational forces of first, second and third rotatable driveconnectors 118, 120, and 122 of surgical instrument 100 to end effector300. As mentioned above, adapter assembly 200 is configured forselective connection to surgical instrument 100.

As seen in FIGS. 1, 6, 10, and 11 adapter assembly 200 includes anelongate, substantially rigid, elongate body portion 210 having aproximal end 210 a and a distal end 210 b; a transmission housing 212connected to proximal end 210 a of elongate body portion 210 and beingconfigured for selective connection to surgical instrument 100. Theadapter assembly 200 also includes an articulating assembly 230 disposedat the distal end 210 b for coupling to the end effector 300.

In embodiments, the transmission housing 212 may include one or moregear train systems therein for varying a speed/force of rotation (e.g.,increase or decrease) of first, second and/or third rotatable driveconnectors 118, 120, and/or 122 of surgical instrument 100 beforetransmission of such rotational speed/force to end effector 300.

Transmission housing 212 of adapter assembly 200 is configured andadapted to connect to connecting portion 108 a of upper housing portion108 of surgical instrument 100. As seen in FIGS. 1 and 6, transmissionhousing 212 of adapter assembly 200 includes a shaft coupling assembly214 supported at the proximal end 210 a

Adapter assembly 200 may include a first gear train system and a secondgear train system, each disposed within transmission housing 212 andelongate body portion 210. Each gear train system is configured andadapted to vary a speed/force of rotation (e.g., increase or decrease)of first and second rotatable drive connectors 118 and 120 of surgicalinstrument 100 before transmission of such rotational speed/force to endeffector 300. An adapter assembly having multiple gear trains isdisclosed in more detail in a commonly-owned U.S. Pat. No. 8,899,462,the entire contents of which is hereby incorporated by reference herein.

As seen in FIG. 11, adapter assembly 200 may rotatably support first,second, and third drive shafts 218 a, 220 a, 222 a, which include aproximal end connected to transmission housing 212, namely,corresponding rotatable connector sleeve 218, 220, 222. Each of thedrive shafts 218 a, 220 a, 222 a also include a distal end extending toand operatively connected to the articulating assembly 230, as will bediscussed in greater detail below. The elongate body portion 210 ofadapter assembly 200 includes at least three longitudinally extendingchannels through body portion 210. The channels are configured anddimensioned to rotatably receive and support the drive shafts 218 a, 220a, 222 a, which may be connected to respective gear systems (not shown).Each of the drive shafts 218 a, 220 a, 222 a are elongate andsufficiently rigid to transmit rotational forces from transmissionhousing 212 to articulating assembly 230, which are used to drive theend effector 300 as described in further detail below.

FIGS. 12-16 illustrate components and operation of the end effector 300.End effector 300 includes a pair of jaw members, which include acartridge assembly 308 and an anvil 306. Cartridge assembly 308 housesone or more fasteners 433 (FIG. 13) that are disposed therewithin and isconfigured to deploy the fasteners 433 upon firing of instrument 100.The anvil 306 is movably (e.g., pivotally) mounted to the end effector300 and is movable between an open position, spaced apart from cartridgeassembly 308, and a closed position wherein anvil 306 is in closecooperative alignment with cartridge assembly 308, to thereby clamptissue.

Referring to FIG. 13, a disassembled view of the end effector 300 isshown. The end effector 300 also includes a carrier 431 having anelongate channel 411, a base 412 and two parallel upstanding walls 414and 416 which include several mounting structures, such as notches 439,for supporting the cartridge assembly 308 and the anvil 306. Alongitudinal slot 413 extends through the elongate channel 411.

The carrier 431 also includes a plate cover 415 disposed on a bottomsurface thereof. The plate cover 415 is configured to frictionallyengage with channel 411 of the carrier 431 and functions to protecttissue from moving parts along the exterior of carrier 431. The carrier431 also includes a pair of tabs 407 and 409 disposed at a proximal endof respective walls 414, 416, and being configured for coupling to ahousing portion 410 of end effector 300.

The carrier 431 also includes a holder plate 402 disposed on a topsurface thereof. The holder plate 402 is configured to frictionallyengage the carrier 431 and the cartridge assembly 308 to secure thefasteners 433 and pushers 437 therein. The holder plate 402 includes apair of distal wings 402 a and a pair of proximal wings 402 b configuredto engage distal tabs 436 a and proximal tabs 436 b of the cartridgeassembly 308, respectively. The distal wings 402 a of the holder plate402 are also configured and dimensioned to engage slots 439 a disposedat a distal end of the carrier 431 thereby securing the cartridgeassembly 308 to the carrier 431.

With continuing reference to FIG. 13, the distal portion of channel 411supports the cartridge assembly 308 which contains the plurality ofsurgical fasteners 433 and a plurality of corresponding ejectors orpushers 437. End effector 300 includes an actuation sled 440 havingupstanding cam wedges 444 configured to exert a fastener driving forceon the pushers 437, which drive the fasteners 433 from cartridgeassembly 308, as described in more detail below. Cartridge assembly 308is maintained within channel 411 by lateral struts 436 whichfrictionally engage corresponding notches 439 formed in the uppersurfaces of channel walls 414 and 416. These structures serve torestrict lateral, longitudinal, and elevational movement of thecartridge assembly 308 within channel 411. In any of the embodimentsdisclosed herein, the cartridge assembly 308 can be removable andreplaceable so that the end effector 300 can be reused within aparticular surgery allowing for multiple firings of a single endeffector 300.

A plurality of spaced apart longitudinal slots (not shown) extendthrough cartridge assembly 308 and accommodate the upstanding cam wedges444 of actuation sled 440. The slots communicate with a plurality ofpockets 442 within which the plurality of fasteners 433 and pushers 437are respectively supported. The pushers 437 are secured by a pusherretainer (not shown) disposed below the cartridge assembly 308, whichsupports and aligns the pushers 437 prior to engagement thereof by theactuation sled 440. During operation, as actuation sled 440 translatesthrough cartridge assembly 308, the angled leading edges of cam wedges444 sequentially contact pushers 437 causing the pushers to translatevertically within slots 446, urging the fasteners 306 therefrom. Thecartridge assembly 308 also includes a longitudinal slot 485 to allowfor a knife blade 474 to travel therethrough, as described in moredetail below.

With continuing reference to FIGS. 13 and 14, the end effector 300includes an anvil cover 435 disposed over the anvil 306. The anvil cover435 protects tissue from moving parts along the exterior of anvil 306.The anvil cover 435 includes opposed mounting wings 450 and 452 whichare dimensioned and configured to engage detents 454 and 456 of theanvil 306, respectively. The mounting wings 450 and 452 function toalign the anvil 306 with the cartridge assembly 308 during closure. Theanvil 306 and the cover 435 are configured to remain in an openconfiguration until closed, as described in more detail below.

The anvil 306 is pivotally coupled to the carrier 431. The carrier 431includes a pair of openings 421 and 422 formed in respective tabs 407,409. The anvil cover 435 also includes a pair of opposed openings 457and 459 found therein. A pivot pin 417, or a pair of pins, passesthrough the openings 421, 422, 457, and 459 allowing for pivotalcoupling of the anvil 306 to the carrier 431 and the cartridge assembly308.

As seen in FIGS. 13 and 14, end effector 300 further includes an axialdrive screw 460 for transmitting the rotational drive forces exerted bythe second drive shaft 220 a, as described in further detail below, toactuation sled 440 during a stapling procedure. Drive screw 460 isrotatably supported in carrier 431 and includes a threaded portion 460 aand a proximal engagement portion 460 b. The drive screw 460 isrotatably secured by a thrust plate 410 b within the distal housingmember 410 such that the drive screw 460 may be rotated relative to thecarrier 431. Distal housing member 410 of the end effector 300 iscoupled to the proximal end of the carrier 431 via pivot pin 417. Thehousing member 410 includes a bore 414 (FIG. 14) defined therethroughthat houses the engagement portion 460 b therein. The distal tip of thedrive screw 460 rests in a recess defined in the channel 411 of thecarrier 431.

As shown in FIGS. 13-15, the drive screw 460 is coupled to a drivelinkage 600, which mechanically engages the second drive shaft 220 a, asdescribed in further detail below, and the drive screw 460 of endeffector 300. The drive linkage 600, disposed within the housing portion410, is off-axis with respect to the drive screw 460. In particular, thelongitudinal axis defined by the drive linkage 600 is at a non-parallel(e.g., non-zero angle) angle with respect to a longitudinal axis definedby the drive screw 460. In embodiments, the drive linkage 600 may bedisposed along the same longitudinal axis as the drive screw 460.

With reference to FIG. 15, the drive linkage 600 includes a proximalengagement portion 601 and a distal engagement portion 603. The proximalengagement portion 601 is configured to be engaged by a coupling member515, and the distal engagement portion 603 is dimensioned and configuredto engage the proximal engagement portion 460 b of drive screw 460. Inparticular, the engagement portion 601 includes a faceted surface, whichis configured and dimensioned to interface with a socket 516 of thecoupling member 515, which has a corresponding faceted surface. Theengagement portion 603 also includes a faceted surface, which isconfigured and dimensioned to interface with a socket 460 c of theengagement portion 460 b, which has a corresponding faceted surface. Themechanical coupling of the engagement portions 601 and 603 with thesockets 516 and 460 c, respectively, occurs via abutment of the malefaceted surfaces of the engagement portions 601 and 603 withcorresponding female faceted socket 516 and 460 c, which allows fortransfer of rotational motion of the coupling member 515 to the drivelinkage 600 and, in turn, to the drive screw 460. In embodiments, thedrive linkage 600 may mechanically interface with the drive screw 460and the coupling member 515 using any other suitable mechanicalcoupling, e.g., pinned.

With reference to FIGS. 13 and 14, end effector 300 further includes adrive beam 462 disposed within carrier 431. The drive beam 462 includesa vertical support strut 472 and an abutment surface 476, which engagesthe knife blade 474, which in turn, engages the actuation sled 440. Thedrive beam 462 also includes a cam member 480 disposed on top of thevertical support strut 472. Cam member 480 is dimensioned and configuredto engage and translate with respect to an exterior camming surface 482of anvil 306 to progressively clamp the anvil 306 against body tissueduring firing.

A longitudinal slot 484 extends through the anvil 306 to accommodate thetranslation of the vertical strut 472. This allows the cam member 480 totravel in between the cover 435 and anvil 306 during firing. Inembodiments, the anvil cover 435 may also include a correspondinglongitudinal slot (not shown) formed on an underside thereof and issecured to an upper surface of anvil 306 to form a channel therebetween.

The drive beam 462 includes a retention portion 488 having a threadedbore 489 defined therethrough. The drive screw 460 is threadably coupledto the retention portion 480 through the bore 489, such that as thedrive screw 460 is rotated, the drive beam 462 travels in a longitudinaldirection along the longitudinal axis defined by the drive screw 460.

In use, as the drive screw 460 is rotated in a clock-wise direction, thedrive beam 462 travels in a distal direction closing the anvil 306 asthe cam member 480 pushes down on the camming surface 482 thereof. Thedrive beam 462 also pushes the sled 440 in the distal direction, whichthen engages the pushers 437 via the cam wedges 444 to eject thefasteners 433. The drive beam 462 may be made of any suitable firstmaterial including, but not limited to, plastics, metals, andcombinations thereof. The first and second materials may be either sameor different.

The knife blade 474 travels slightly behind actuation sled 440 during astapling procedure to form an incision between the rows of fastener bodytissue. As the drive beam 462 is driven in the distal direction, theabutment surface 476 of the vertical strut 472 pushes the knife blade474, which then pushes sled 440 in the distal direction to eject thefasteners 433 and simultaneously dissect tissue with the knife blade474. The knife blade 474 and the drive beam 462 travel through thelongitudinal slots 484 and 485. The drive beam 462 closes the anvil asit is driven in the distal direction and also pushes the sled 440,which, in turn, ejects the fasteners 433 ahead of the knife blade 474.As the fasteners 433 are ejected they are deformed again thetissue-contacting (e.g., underside) surface of the anvil 306 having aplurality of anvil pockets (not shown).

With reference to FIGS. 11, 12, and 14-17A, the articulating assembly230 is shown. The assembly 230 includes a distal joint member 232 forcoupling to a proximal end of the end effector 300 and a proximal jointmember 234 coupled to the distal end 210 b of the body portion 210.

With reference to FIGS. 13 and 16-21 the housing portion 410 of the endeffector 300 includes one or more posts 410 a for insertion into one ormore corresponding bores 580 a within a socket 580. The socket 580 isrotationally disposed within the joint member 232. In particular, thesocket 580 is disposed within a spacer 232 a and includes a texturedring 232 b disposed on an outer surface thereof. This allows the socket580 to be rotated about the longitudinal axis “C-C” (FIG. 12) by a shaft513 that is longitudinally arranged within the joint member 232, asdescribed in further detail below.

The shaft 513 includes one or more facets 513 a such that the shaft 513is keyed to a central bore 580 b of the socket 580. This allows forrotation of the socket 580 along with the shaft 513. As shown in FIG.16, during insertion the proximal engagement portion 601 of the drivelinkage 600 also engages the socket 516 of the coupling member 515,which actuates the drive screw 460 as described in further detail below.

With reference to FIGS. 17A-19, the proximal joint member 234 and thedistal joint member 232 are configured and dimensioned as a clevis tointerface with a pin 505. The pin 505 includes one or more longitudinalfacets 505 a along at least a portion of the pin 505. The proximal jointmember 234 of the neck assembly 230 includes a pair of opposing arms235, 237 including a pair of opposing circular bores 235 a, 237 a,respectively, allowing the pin 505 to be rotationally coupled within thebores 235 a, 237 a of opposing arms 235, 237. With reference to FIGS.17A-B, the joint member 232 of the assembly 230 also includes a pair ofopposing arms 239, 241 including a pair of opposing bores 239 a, 241 a.With reference to FIG. 17B, each of the bores 239 a, 241 a includes afacet 239 b, 241 b, such that when the pin 505 is inserted into thebores 235 a, 237 a, 239 b, 241 b, the pin 505 can rotate freely withinthe bores 235 a, 237 a. This secures the joint member 232 to the pin 505about the bores 239 a, 241 a via mating of the facet 505 a of the pin505 with the facets 239 b, and 241 b. Since the pin 505 is keyed to thebores 239 a, 241 a of the joint member 232 and is free-floating withinthe bores 235 a, 237 a of the proximal joint member 234, the jointmember 232 along with the end effector 300 may be freely rotated withrespect to the proximal joint member 234 about a articulation axis “B-B”(FIG. 12) defined by the pin 505 as shown in FIG. 22 and described infurther detail below.

With reference to FIGS. 17A and 18, the assembly 230 also includes thesecond (e.g., actuating/firing) drive shaft 220 a, which may be axiallyrotatable within the body portion 210. The drive shaft 220 a includes asecond gear element 502 coupled thereto and configured to rotatetherewith about a longitudinal axis defined by the drive shaft 220 a.The gear element 502 is meshingly engaged with a first transfer gearelement 504. The gear element 504 is held in position by the pin 505 andis configured to rotate about the pin 505.

The gear element 504 is also meshingly engaged with a gear element 506within the joint member 232. The gear elements 502, 504, 506 are bevelgears allowing for meshing engagement thereof even as the joint member232 and the end effector 300 are pivoted with respect to the bodyportion 210. The gear element 502 rotates about a longitudinal axisparallel with the axis “A-A.” The gear element 504 rotates about theaxis “B-B” (FIG. 12) and the gear element 506 rotates about alongitudinal axis parallel with the axis “C-C” (FIGS. 2 and 10). Thegear element 506 is connected to a gear element 510 by a shaft 508. Thegear element 506, the gear element 510, and the shaft 508 rotate withinthe joint member 232 about a longitudinal axis defined by the centralaxis of the shaft 508. The gear element 510 is, in turn, meshinglyengaged with a gear element 512 that rotates about the shaft 513 that islongitudinally arranged within the joint member 232. The gear element512 is meshingly engaged with a gear element 514 of the coupling member515. The coupling member 515 includes a shaft portion that extendsdistally to the socket 516, which is coupled to drive linkage 600 asdescribed above. Rotation of the drive shaft 220 a results in rotationof the gear elements 502, 504, 506, 510, 512, 514 and the socket 516,which in turn, rotates the drive screw 460 via the drive linkage 600thereby actuating the firing process as described above.

With continued reference to FIGS. 16-21, the assembly 230 also includesthe third (e.g., rotating) drive shaft 222 a, which may be axiallyrotatable within the body portion 210. The drive shaft 222 a includes athird gear element 552 coupled thereto and configured to rotatetherewith about a longitudinal axis defined by the drive shaft 222 a.The gear element 552 is meshingly engaged with a second transfer gearelement 554. The gear element 554 is held in position by the pin 505 andis configured to rotate about the pin 505.

The gear element 554 is also meshingly engaged with a gear element 556within the joint member 232. The gear elements 552, 554, 556 are bevelgears allowing for meshing engagement thereof even as the joint member232 and the end effector 300 are pivoted with respect to the bodyportion 210. The gear element 552 rotates about a longitudinal axisparallel with the axis “A-A.” The gear element 554 rotates about theaxis “B-B” and the gear element 556 rotates about a longitudinal axisparallel with the axis “C-C.” Use of the bevel gears, namely, the gearelements 502, 504, 506, 552, 554, 556, allows for tightest possible 90°bend angle of the joint member 232 during articulation with respect tothe body portion 210 of the adapter assembly 200 as shown in FIG. 23,which shows the joint member 232 pivoted with respect to the jointmember 234.

With continued reference to FIGS. 16-21, the gear element 556 isconnected to a gear element 560 by a shaft 558. The gear element 556,the gear element 560, and the shaft 558 rotate within the joint member232 about a longitudinal axis defined by the central axis of the shaft558. The gear element 560 is, in turn, meshingly engaged with a gearelement 562, which is fixedly coupled to the shaft 513, such thatrotation of the gear element 562 results in rotation of the shaft 513.As described above, the socket 580 is securedly coupled to the shaft513, such that as the shaft 513 is rotated in either clockwise orcounterclockwise direction about the longitudinal axis “C-C” the socket580 is also rotated in the same direction. Since the end effector 300 isengaged with the socket 580 as described above, the end effector 300 issimilarly rotated by the shaft 513. The end effector 300 is configuredto rotate about its own longitudinal axis in this manner.

The present disclosure also provides for a rotation lockout assembly 700for preventing rotation of the end effector 300 during firing. Thisallows for prevention of tissue damage due to the torque generatedduring the firing process which would otherwise backfeed the gearswithin the neck assembly 230 and inadvertently rotate the end effector.

With reference to FIGS. 13, 15, and 17A, the housing 410 may include adistal portion 427 a and a proximal portion 427 b interconnected by abolt 429 with the bore 423 a (FIG. 13) defined therethrough. The shaft513 disposed within the joint member 232 includes a bore 423 b (FIG.17A) defined therethrough. The bores 423 a and 423 b are in longitudinalalignment.

With reference to FIGS. 15-17A, the lockout assembly 700 includes a pushrod 702 disposed within the bore 423 a and a locking member 704 disposedwithin the joint member 232. The locking member 704 includes a rod 706disposed within the bore 423 b. The distal end of the rod 706 is incontact with a proximal end of the push rod 702, such that longitudinalmovement of either the push rod 702 or the locking member 704 istranslated therebetween. The locking member 704 also includes one ormore lock lugs 707 configured and dimensioned to meshingly engage thegear element 562. The locking mechanism 700 also includes a spring 708,which is coupled to the joint member 232 and pushes the locking member704 in a distal direction.

With reference to FIG. 16, prior to insertion of the end effector 300into the joint member 232, the locking member 704 is engaged with thelock lug 707 thereof preventing actuation of the coupling member 515. Asshown in FIGS. 15 and 18, after insertion of the end effector 300, thedrive beam 462 is in its proximal most position since it has not beenfired and therefore abuts the distal end of the push rod 702. This movesthe push rod 702 proximally, which also moves the locking member 704 ina proximal direction to disengage the lock lug 707 from the teeth of thegear element 562. The disengagement of the locking member 704 allows forrotation of the shaft 513, the socket 580, and in turn, the end effector300 in either clockwise or counterclockwise direction about thelongitudinal axis “C-C.”

Once the desired rotational position is achieved firing may be commencedas described above. Firing moves the drive beam 462 distally, whichallows the push rod 702 along with the locking member 704 to traveldistally due to the biasing forces of the spring 708 as shown in FIG.24. This moves the lock lug 707 of the locking member 704 intoengagement with the gear element 562 preventing rotation of the endeffector 300 during the firing process.

With reference to FIGS. 17A, 18 and 25-27, the assembly also includesthe first (e.g., pivoting) drive shaft 218 a, which may be axiallyrotatable within the body portion 210. The drive shaft 218 a includes afirst gear element 570 at its distal end, which is configured as a wormgear. The gear element 570 is meshingly engaged with a pivoting gearelement 572, which is configured as a worm wheel drive. The gear element572 includes a bore 574 a therethrough having a facet 574 b. The gearelement 572 is disposed between the gear elements 504, 554 and issecured to the pin 505 about the bore 574 a via mating of the facet 505a of the pin 505 with the facet 574 b of bore 574 a of gear element 572in a keyed relationship. Thus, the gear element 572 is secured to thepin 505 along with the joint member 232, which allows for rotation ofthe joint member 232 along with the end effector 300 with respect to thebody portion 210 about the articulation axis “B-B” defined by the pin505 as described in further detail below.

As shown in FIGS. 25-27, articulation of the joint member 232 about thearticulation axis “B-B” is imparted by rotation of the drive shaft 218 aabout its longitudinal axis and simultaneous longitudinal movement ofthe drive shaft 218 a along its longitudinal axis, which in turn,rotates the gear element 572 via the gear element 570. Simultaneousrotational and longitudinal movement of the drive shaft 218 a may beaccomplished via a complementary worm gear mechanism at its proximalend. Since the gear element 572 is securedly coupled to the pin 505,rotation of the gear element 572 rotates the pin 505 and the jointmember 232, which is also securedly coupled thereto as described above.The drive shaft 218 a includes a thrust plate 218 b that acts as a stopmember preventing longitudinal movement of the drive shaft 218 a beyonda certain point, which in turn, prevents rotation of the joint member232 and the end effector 300 beyond a desired stopping point. Inembodiments, the joint member 232 may be rotated about the articulationaxis “B-B” up to about 300°, with about 150° in either direction fromthe first aligned position in which the second longitudinal axis “C-C”is substantially aligned with the first longitudinal axis “A-A.” Infurther embodiments, the joint member 232 may be rotated about thearticulation axis “B-B” up to about 180°, with about 90° in eitherdirection from the first aligned position.

The gearing relationship between the gear elements 570 and 572 allowsfor precise pivoting of the end effector 300 with respect to the adapterassembly 200. In addition, the gear elements 570 and 572 provide for agearing reduction due to a worm gear/worm wheel drive relationship,thereby obviating the need for additional gear reduction mechanisms atthe proximal end of the adapter assembly 200.

Referring to FIGS. 28-30, another embodiment of an articulating assembly1230 provided in accordance with the present disclosure including alongitudinally translating drive shaft 1218 a. Articulating assembly1230 is substantially similar to articulating assembly 230 and includesmost of the components of articulating assembly 230, which are notdescribed below to avoid repetition. Drive shaft 1218 a is operativelydisposed within body portion 210. Drive shaft 1218 a includes a firstgear element 1570 that engages pivoting gear element 572. Inembodiments, gear element 1570 may be configured as a toothed rack thatengages pivoting gear element 572 in a rack and pinion relationship, asbest illustrated in FIG. 30.

With reference to FIGS. 31-33, articulation of joint member 232 aboutarticulation axis “B-B” (FIG. 28) is imparted by longitudinaltranslation of drive shaft 1218 a along its longitudinal axis, which isparallel to the longitudinal axis “A-A” (FIG. 10). Longitudinal movementof drive shaft 1218 a, in turn, rotates pivoting gear element 572 viafirst gear element 1570. The longitudinal translation of drive shaft1218 a may be accomplished via a drive mechanism described above withrespect to drive shaft 218 a. First gear element 1570 may extend alongdrive shaft 1218 a such that a portion of first gear element 1570 isadjacent a proximal end of drive shaft 1218 a. Since pivoting gearelement 572 is securely coupled to pin 505, rotation of pivoting gearelement 572 rotates pin 505 and joint member 232, which is also securelycoupled thereto as described above.

Drive shaft 1218 a also includes a thrust plate 1218 b that acts as astop member preventing longitudinal translation of drive shaft 1218 abeyond certain limits (e.g., a proximal limit 1219 a or a distal limit1219 b), which in turn, prevents rotation of joint member 232 and endeffector 300 beyond a desired point. In embodiments, joint member 232may be pivoted about the articulation axis “B-B” to a first and secondpivoted positions in either direction from a first aligned position inwhich the second longitudinal axis “C-C” (FIG. 28) is substantiallyaligned with the first longitudinal axis “A-A” (FIG. 10). The first andsecond pivoted positions may be up to about 300°, with about 150° ofpivot in either direction from the first aligned position. In furtherembodiments, joint member 232 may be pivoted about the articulation axis“B-B” up to about 180°, with about 90° of pivot in either direction fromthe first aligned position.

The gearing relationship between gear elements 1570 and 572 allows forprecise pivoting of end effector 300 with respect to adapter assembly200. In addition, the interaction of gear elements 1570 and 572 mayprovide for a back drive mechanism that permits external forces exertedon an end effector attached to articulating neck assembly 1230 about thepivot axis to back drive the motor until a solid stop is reached (i.e.,thrust plate 1218 b reaching proximal or distal limit 1219 a, 1219 b).The solid stop may correspond to the first or second rotated positionsof end effector 300. The back drive mechanism may also include a forcemultiplier configured to reduce the force exerted on the motor by theback drive mechanism. The force multiplier may be from about 1 to about40, in embodiments, from about 5 to about 20.

In the examples discussed above, the hand-held instrument handle houseda removable and replaceable and/or rechargeable battery, as well as amotor and computer and memory components. A removable and replaceableadapter assembly corresponds to one or more end effector configurations,the end effectors being removable and replaceable. For example, anadapter is configured for use with circular stapling reload endeffectors in various sizes, and with or without various other featuressuch as suction and irrigation, visualization, etc. Other adapters areavailable for use with linear surgical stapling reloads come in varioussizes, configurations, possibly having other features such as dissectiontips and/or pre-loaded surgical buttress material. In the examplesabove, the handle may be disposable, for single-procedure use, orsterilizable and re-used for a prescribed number of procedures.

In another example shown in FIG. 34, a surgical stapling handle 2010contains a removable and re-usable motor and battery (not shown), andthe handle housing 2012 itself opens and closes to receive thosecomponents. This may extend the useful life of the motor, which can behoused in the handle housing in a sealed fashion, avoiding the need tosterilize the motor, the battery, etc. The handle housing 2012 isopenable like a shell, as shown and is re-sterilizable. The handlehousing carries a series of buttons 2014 and controls for actuatingarticulation, clamping of tissue, stapling of tissue and cutting of thetissue. These buttons, as well as various indicators (such as lights,screens and the like) can be as discussed above or similar thereto. Thecontroller desirably contains a microprocessor and memory componentsthat record information concerning the use of the instrument and caninteract with sensor provided in the other components such as the endeffector reload, adapter, staple cartridge assembly, etc.

It is contemplated that the adapter assembly 2016 can be removable, asmentioned above, or it can be permanently attached to the handle. Theadapter assembly includes a drive mechanism which has mechanicalcomponents for manipulating the end effector (FIG. 34A), such asarticulation, opening and closing of jaws, etc. As shown in FIG. 35, theadapter assembly 2016 has a proximal end 2018 with a knob 2020, and adistal end 2022 that can be attached to a surgical stapling end effectorreload 3010. The proximal end 2018 has a lead screw 2026 with a proximalend 2028 that is accessible at the proximal end 2018 of the adapterassembly 2016. An inner tube 2030 is threadably engaged with (i.e., ithas helical grooves) the lead screw, which also has helical threads sothat rotation of the lead screw 2026 will translate the inner tube 2030in a proximal or distal direction. There is a thrust bearing 2032 (FIG.36) at the proximal end of the lead screw so that it is mounted in theknob 2020. A pusher 2034 is attached to the distal end 2026 a of thelead screw and is connected to a bar 2036 through a pin, screw, or thelike. The inner tube 2030, thrust bearing 2032, and pusher 2034 can alsobe seen in FIGS. 39A and 39B

The adapter assembly has a drive mechanism inside an elongate shaft thatarticulates. As shown in FIG. 37, the distal end 2022 of the adapterassembly 2016 has a pair of bar guides 2038, one each on either side ofa bar 2036, and adjacent to the bar guides is a pair of blowout plates2046 that are next to the bar guides, but distal to them. The bar itselfis made of a plurality of layers, or stainless steel or equivalentmaterial, that are stacked against one another. At a distal end 2040 ofthe bar, a beam is attached to the bar. The beam shown is an I-beam 2042having an upper flange 2042 a and a lower flange 2042 b is attached. Thebar is further supported by a support block 2044 that has an opening2046 so that it surrounds the bar, and the blowout plates 2046. Thesupport block is curved in shape, with the convex side of the supportblock facing proximally, and is made of a strong material like stainlesssteel. As seen in FIG. 37, the blowout plates each have a distal end2046 a that form a flange 2048 for being received in a slot in amounting member 2050. The mounting member 2050 forms the distal end ofthe adapter assembly 2016 and can be attached to the end effectorreload. The mounting member 2050 also has an arcuate slot for receivingand supporting the support block 2044, and also allowing the supportblock 2044 to move so that the assembly (the bar, blowout plates,support block) move off-center with respect to the adapter assembly whenthe end effector reload is articulated and pivoted with respect to theadapter (see FIG. 38). In such movement, the bar guides 2038 are movedas well (see FIG. 39). The bar, the pair of bar guides, the pair ofblowout plates, and the support block are pivotable from a centralposition in the adapter assembly to an off-center position in theadapter assembly.

When the device is articulated, the distal ends of the bar guides pivotoff-center, supporting the blowout plates and the plurality of layersforming the bar. When the guides pivot off-center, it creates a largeradius for the bar to be driven through, reducing stress on the bar, andthe layers making up the bar. The bar guides are separate members, butthey pivot together. The assembly works in the same way when articulatedin the opposite direction.

I-beam 2042 and bar 2036 are moved by the inner tube 2030 in a distaldirection to effect the closing of the end effector jaw members ontotissue, and to fire staples and cut tissue. (FIGS. 39A and 39B). The endeffector reload 3010 has an anvil assembly 3012, a cartridge assembly3014, and a channel 3016 for receiving the cartridge assembly. Theentire end effector reload 3010 can be attached to the adapter assembly2016, and removed and replaced after use. (FIG. 46). The anvil assembly3012 can be one or more parts machined and/or welded together, andhaving an anvil plate 3012 a with recesses shaped for forming thestaples into a closed shape when they are driven against the anvil plate3012 a. The staple cartridge assembly 3014 is attached to the channel3016 and has an upper surface with slots (also seen in FIG. 50) thathouse the unformed staples and allow their ejection from the cartridgeassembly 3014 and into tissue.

The anvil assembly 3012, staple cartridge assembly 3014, and channel3016 have slots that allow the passage of the I-beam 2042 and bar 2036.The layers of the bar 2036 are dimensioned so that they extend into boththe slot in the anvil assembly 3012 and the slot in the channel 3016.The staple cartridge assembly 3014 has a sled 3018 that carries a knife3020 rotatably supported on the sled. The knife can be biased in anupward position for cutting tissue, or it can be biased in a downwardposition where it does not access tissue, and/or the knife 3020 can bemoved by a feature on the I-beam 2042. As shown in FIG. 40, the featureof the I-beam can be a slot 3022 for camming a protrusion 3024 on theknife 3020. When the bar and I-beam are moved distally, the engagementof the flanges 2042 a and 2042 b of the I-beam with the anvil assemblyand channel move the anvil assembly, staple cartridge assembly, andchannel into approximation to engage tissue. In further movementdistally, the I-beam 2042 pushes the sled 3018 and knife 3020 distally.(See FIGS. 40 and 40A; see also a substantially similar embodimentdescribed in greater detail below and illustrated in at least FIGS.52-63). The sled interacts with pushers in the staple cartridge assemblyto drive the staples out of the slots. In other examples, the knife canbe formed directly on the I-beam 2042.

The proximal end 3030 a of the articulation mechanism 3030 of theadapter assembly 2016 is shown in FIG. 41. A cylindrical articulationnut 3032 having threads on its proximal end 3034. An input shaft 3036with corresponding threads is enmeshed with the threads of the nut 3032.The rotating shaft 3036 will rotate the nut 3032 through the operationof the threads. The interior of the nut 3032 is hollow and also has ahelical groove 3038. The groove 3038 is engaged with a groove 3040 onthe outside of a screw 3042 (FIG. 42) disposed inside the nut 3032. Whenthe nut 3032 rotates, the screw moves distally or proximally, to move anarticulation link 3044. In this way, distal movement of the link willarticulate or pivot the end effector in one direction, and proximalmovement of the link 3044 will articulate or pivot the end effector inthe other direction.

The distal end 3030 b of the articulation mechanism 3030 of the adapterassembly 2016 is shown in FIG. 43. The articulation link 3044 ends in aconnection to a second link which is a short link 3048, via a pin. Theshort link is curved and also pinned to the mounting member 2050 at anoff-center location. (FIG. 44). The mounting member 2050 is connected tothe adapter assembly 2016 at a pin 3050 a and the mounting member 2050pivots about the pin 3050 when the links 3044, 3048 are moved. (SeeFIGS. 44 and 45).

The adapter assembly 2016 proximal end 2018 knob 2020 houses a mechanismfor rotating the entire adapter assembly about its own longitudinal axis“A”. A rotation input shaft 3052 rotates a gear 3054 that is enmeshedwith a ring gear 3055. When the input shaft rotates, it rotates the knob2020, outer tube 2021, and everything attached to it. (FIG. 45A).

FIG. 46 shows the attachment of the end effector reload 3010 to theadapter assembly. The anvil assembly 3012 has a semi-cylindricalproximal end 3012 a that forms tissue stops 3060. The tissue stops 3060form walls, one on each side of the reload 3010. On an interior surfaceof each tissue stop 3060 a locking tab 3062 is defined. The locking tabseach have an extension 3062 a that is received in a connection featureof the mounting member. The connection feature of the mounting member isa pair of keyways 2051 defined in the mounting member 2050. (FIGS. 46,47, 48). The keyways each form a slot that receives the extension 3062 ato lock the reload onto the adapter assembly. The keyways slots areupwardly open, so that the end effector reload is locked onto theadapter assembly through movement of the reload downwardly. (FIGS. 47and 48). Spring fingers 2051 a engage the locking tab extensions. (FIG.48A).

The example described above has a staple cartridge assembly that is notintended to be removed and replaced in the end effector reload 3010. Infurther examples, the adapter assembly 2016 and end effector reload 3010are as described above, except that the end effector reload has aremovable and replaceable staple cartridge assembly. As shown in FIGS.49 and 50, the staple cartridge assembly 3014″ has a snap-fitarrangement at its proximal end, formed by a rearward-facing opening3014 a″ in the staple cartridge body 4015 and a corresponding opening3018 a″ in the support tray. These openings engage a boss 3016 a″ in thechannel 3016″ in a snap-fit relationship. In this way, the end effectorreload, adapter assembly, and stapler handle can be reused to fireanother set of staples, without replacing the end effector reload. Asthe length of the staple lines depends on the selection of the endeffector reload, that component must be replaced to change the length ofthe staple lines formed in tissue. However, the size of the staples, andthe arrangement of staples (more than one staple size, or all the samesize staples), whether there is a pre-loaded buttress or curved tip orother feature, can be changed by changing the selection of the staplecartridge assembly 3014″. A manually actuated stapler handle, in aninstrument having a removable and replaceable staple cartridge assembly,is disclosed in U.S. Pat. No. 9,016,539, the entire disclosure of whichis hereby incorporated by reference herein.

In a further alternative example of an articulation mechanism in theadapter assembly, FIG. 51 shows an articulation mechanism having athreaded engagement in the distal portion of the adapter assembly 4016.The articulation mechanism is as described above, and has anarticulation link 4044, and a short link 4048, connected to one anotherby a pin 4046. The drive shaft 4049 extends to the distal end of theadapter assembly 4016 and forms a series of threads 4050 on its distalend. The threads 4050 are engaged with threads on the articulation linkand are used to translate the articulation link 4044 when the driveshaft 4049 rotates.

Turning now to FIGS. 52-63, another embodiment of an end effector isgenerally referred to as end effector 5000. End effector 5000 includes atool assembly 5100 (e.g., a multi-use loading unit or MULU) and acartridge assembly 5200 that mounts to tool assembly 5100. Similar totool assembly 304 above, tool assembly 5100 generally includes a firstjaw member 5110 and a second jaw member 5112 that are pivotally coupledtogether. Second jaw member 5112 supports cartridge assembly 5200, whichmay be selectively replaceable, a lead screw 5114, and an I-beam 5116(see FIG. 61) that is threadably coupled to lead screw 5114 toselectively advance I-beam 5116 along cartridge assembly 5200 forapproximating first and second jaw members 5110, 5112 and/or firing endeffector 5000. End effector 5000 is configured to couple to an adapterassembly 200 x that selectively couples to surgical instrument 100 (seeFIG. 52A).

With reference to FIG. 54, cartridge assembly 5200 of end effector 5000includes a cartridge holder 5210 and a cartridge 5220 having atissue-contacting surface 5222. Cartridge holder 5210 and cartridge 5220of cartridge assembly 5200 support pushers 5230, fasteners 5240supported on pushers 5230, and a sled assembly 5250 that is slidablyadvanceable along cartridge assembly 5200 to fire fasteners 5240 fromcartridge 5220 as pushers 5230 cam along sled assembly 5250.

As seen in FIGS. 55-59, sled assembly 5250 includes an actuation sled5252 and a knife assembly 5254 pivotally supported on actuation sled5252 between a first position and a second position. Actuation sled 5252includes a plurality of upstanding cam wedges 5252 a separated by aknife mount 5252 b and configured to exert a fastener driving force onpushers 5230 (FIG. 54). Knife mount 5252 b defines a spring bore 5252 cand a vertical channel 5252 d therein. Knife mount 5252 b furtherincludes a pivot pin 5252 e that extends transversely from a sidewall5252 f of knife mount 5252 b to pivotally support knife assembly 5254thereon, a stabilizing finger 5252 g that extends proximally from knifemount 5252 b and is positioned to provide lateral stability to knifeassembly 5254 when the knife assembly 5254 is disposed in the secondposition, and a blocking arm 5252 h that extends over knife assembly5254 and is positioned to support knife assembly 5254 in the secondposition to facilitate tissue cutting. Knife assembly 5254 includes aspring 5254 a (e.g., compression spring) that is received within springbore 5252 c of knife mount 5252 b, and a knife 5254 b engaged withspring 5254 a. As indicated by arrow “A,” knife 5254 b of knife assembly5254 is pivotally supported on pivot pin 5252 e to enable knife 5254 bto pivot (e.g., rotate) about pivot pin 5252 e between a first position(FIG. 55), in which knife 5254 b is disposed below tissue-contactingsurface 5222 of cartridge 5220 to prevent tissue cutting, and a secondposition (FIG. 56), in which knife 5254 b is raised abovetissue-contacting surface 5222 of cartridge 5220 to enable tissuecutting for tissue supported on tissue-contacting surface 5222.

Knife 5254 b of knife assembly 5254 includes a knife arm 5254 c thatsupports a blade 5254 d on a knife head 5254 x disposed a proximal endportion of knife 5254 b. Knife 5254 b further defines a pivot hole 5254e on a distal end portion thereof that receives the pivot pin 5252 e ofknife mount 5252 b. Knife arm 5254 c includes an arched configurationand is positioned to engage a bottom surface of blocking arm 5252 h ofknife mount 5252 b to prevent knife 5254 b from pivoting beyond thesecond position of knife 5254 b. Knife arm 5254 c further includes adistal foot 5254 f that engages spring 5254 a to enable spring 5254 a tourge knife 5254 b toward the first position in which blade 5254 d ofknife 5254 b is positioned below blocking arm 5252 h of knife mount 5252b (see FIG. 57). Distal foot 5254 f includes an arch 5254 g along whicha distal portion of spring 5254 a cams as knife 5254 b pivots aboutpivot pin 5252 e. Spring 5254 a of knife assembly 5254 is positioned tourge distal foot 5254 f distally to maintain knife 5254 b in the firstposition (e.g., so that blade 5254 d remains below tissue-contactingsurface 5222 of cartridge 5220). Distal foot 5254 f further includes aproximal toe 5254 h that is receivable in vertical channel 5252 d ofknife mount 5252 b as knife 5254 b pivots relative to knife mount 5252 bfrom the first position to the second position.

In operation, illustrated in FIGS. 60-63, I-beam 5116 is advancedbetween first and second jaw members 5110, 5112 to approximate or clampfirst and second jaw members 5110, 5112 together (see FIG. 60). In suchclamped position, a distal surface 5116 a of I-beam 5116 is spaced froma proximal surface 5252 x of actuation sled 5252 of sled assembly 5250,and knife head 5254 x of knife 5254 b of sled assembly 5250 is incontact with a camming surface 5116 b of I-beam 5116. As indicated byarrow “B,” when I-beam 5116 advances distally farther in response torotation of lead screw 5114, as indicated by arrows “R,” knife head 5254x of knife 5254 b of sled assembly 5250 cams upwardly along cammingsurface 5116 b of I-beam 5116 and against spring biasing forces impartedby spring 5254 a of knife assembly 5254. As knife head 5254 x cams alongcamming surface 5116 b of I-beam 5116, knife 5254 b pivots (e.g.,rotates) upwardly and distally, as indicated by arrow “A,” from thefirst position toward the second position (see FIG. 62). As knife 5254 bof knife assembly 5254 moves toward the second position thereof, distalsurface 5116 a of I-beam 5116 approximates proximal surface 5252 x ofactuation sled 5252.

When knife 5254 b is in the second position thereof such that blade 5254d of knife 5254 b is above tissue-contacting surface 5222 of cartridge5220 and distal surface 5116 a of I-beam 5116 is in contact withproximal surface 5252 x of actuation sled 5252, further distaladvancement of I-beam 5116 causes sled assembly 5250 to advance distallythrough cartridge assembly 5200, as indicated by arrow “C,” to fire endeffector 5000 for forming fasteners 5240 and cutting tissue clamped byend effector 5000. Once fired, cartridge assembly 5200 can be removedand replaced for subsequent re-use of end effector 5000.

In some embodiments, knife head 5254 x of knife assembly 5254 mayinclude a guide pin that extends transversely therefrom and that isconfigured to translate through a slot defined in, for example, anI-beam (see e.g., slot 3022 in FIG. 40) to facilitate pivoting movementof knife 5254 b (see e.g., FIGS. 40A and 40B which illustrate a similarembodiment with such a guide pin “GP”).

While persons skilled in the art will understand that the structures andmethods specifically described herein and shown in the accompanyingfigures are non-limiting exemplary embodiments, and that thedescription, disclosure, and figures should be construed merely asexemplary of particular embodiments. It is to be understood, therefore,that the present disclosure is not limited to the precise embodimentsdescribed, and that various other changes and modifications may beeffected by one skilled in the art without departing from the scope orspirit of the disclosure. For example, surgical instrument 100 and/orend effector 300 need not apply staples but rather may apply two partfasteners as is known in the art. Further, the length of the linear rowof staples or fasteners may be modified to meet the requirements of aparticular surgical procedure. Thus, the length of the linear row ofstaples and/or fasteners within a staple cartridge assembly may bevaried accordingly. Additionally, the elements and features shown ordescribed in connection with certain embodiments may be combined withthe elements and features of certain other embodiments without departingfrom the scope of the present disclosure, and that such modificationsand variations are also included within the scope of the presentdisclosure. Accordingly, the subject matter of the present disclosure isnot limited by what has been particularly shown and described.

1. A surgical stapling system comprising: a cartridge assembly includinga cartridge and a sled assembly configured to drive fasteners throughthe cartridge, the cartridge having a tissue-contacting surface, thesled assembly including a knife pivotally coupled to the sled assembly,the knife having a blade, the knife positioned to pivot distally from afirst position where the blade is disposed below the tissue-contactingsurface to a second position where the blade is disposed above thetissue-contacting surface.
 2. The surgical stapling system of claim 1,wherein the sled assembly includes knife mount having a blocking surfacethat extends over the knife and is positioned to support the knife inthe second position.
 3. The surgical stapling system of claim 2, whereinthe knife includes a knife arm that coupled to the knife mount by apivot pin to enable the knife to pivot relative to the knife mount. 4.The surgical stapling system of claim 3, wherein the knife is coupled toa spring that is engaged with the knife mount and positioned to urge adistal foot of the knife arm distally so that the blade, which issupported on a proximal portion of the knife arm, is urged toward thefirst position.
 5. The surgical stapling system of claim 4, wherein theknife mount includes a stabilizing finger that extends from the knifemount to support the knife when the knife is in the second position.